Self-contained popcorn popper

ABSTRACT

A self-contained popcorn popper has an open side provided with an air-flow curtain extending at least partially across the open side and directed inwardly. Effluent from popping flows upwardly into a “U”-shaped vent, through an effluent filter and flows into said air flow curtains to reduce particulate-bearing effluent emitted from the popper cabinet. Heated air is recirculated in a lower warming bin to maintain heat in popped corn dumped from a popping kettle and that air is recirculated in the bin, also to reduce emission of particulars into the environment surrounding the popper.

RELATED APPLICATIONS

The present application is a Divisional application of co-pending U.S.Ser. No. 14/504,854, filed Oct. 2, 2014, which claims priority to U.S.Ser. No. 61/888,267 filed Oct. 8, 2013, the disclosures of which arehereby incorporated herein by reference in their entireties.

FIELD OF THE INVENTION

This invention relates to controlling the emissions of particulates fromfood preparation processes and more particularly to apparatus andmethods for controlling the emission of particulates from popcornpopping operations. The term “controlling” as used herein refers both tothe reduction and the substantial elimination of such particulates, atleast to the extent of detection by current testing procedures andregulations.

BACKGROUND OF THE INVENTION

In the past, popcorn poppers as disclosed in U.S. Pat. No. 7,874,244used a blower and filter combination to capture, from within the poppercabinets, oil, steam, smoke and particulates from the popping process.Within the cabinet, the system would filter said particulates from theair and then exhaust the filtered air to the outside of the poppercabinet.

The amount of particulates not filtered out but permitted by currentstandards or regulations to exhaust to the surrounding air outside thepopper is limited to 5 mg/cubic meter of air discharged from the filtersystem. Also, no visible particulates should be permitted to escape thecabinet per the testing standard from the open areas of the popper.However, for measurement and an actual analysis, there are particulatesfound escaping from these openings that are not accounted for during thetesting because they are not visible, or detectable with currenttechniques.

The emission of particulates from a popcorn popping process, viafiltered or unfiltered air discharging into the surrounding environmentin which a popper operates, is undesirable and can create a number ofultimately significant disadvantages. For example, many movie theatershave adopted digital projection system or are moving in that direction.Discharged particulates from the poppers in the theater can deposit orgather on the components of the equipment or related media, whetherdigital or conventional, adversely affecting or damaging projection andother performance parameters. Some particulates can be troublesome dueto being microscopic in size. Particulate deposits of this nature aredifficult to clean.

In applicant's prior U.S. Pat. No. 7,874,244, a self-contained popperrelieved the particulate discharge disadvantage to some extent bycreating defined airflow within the popper cabinet and filtering outparticulates before that airflow was discharged into the surroundingenvironment.

Particulate components of such discharges were reduced to such an extentthat large capacity poppers with open-sided cabinets could be used topop popcorn and maintain it at a warm temperature, all without thenecessity of connection of the popper to an existing exhaust ductsystem, or of modifying a building or theater by adding necessary butcostly exhaust ductworks. U.S. Pat. No. 7,874,244 is thus expresslyincorporated herein by reference as if fully expressed in writing hereinas exemplary of these considerations. However, further reduction andelimination of particulate emissions is desired.

Thus, while such prior system provided unique and significant advantagesto the industry, as disclosed in that patent, it is now desired toprovide an improved, open, popcorn popper where there are nosignificantly measurable emissions of any air carrying any visible,measurable or significant particulate components.

It is also desirable to take advantage of the natural tendency of thesteam carrying the particulates to rise. In prior systems, the blowerproduced significant flow to draw the steam-borne particulates into thefilter system. The filters for that unit were sized based on the cubicfoot per minute flow produced by the blower.

It is now desired to significantly eliminate the emission of air from anopen popcorn popper, and thus to significantly reduce to an immeasurableor very low level any particulates from a popcorn popper and warmer evenwhere the cabinet housing the cooking kettle and popcorn warming areahas one or more fully open sides.

SUMMARY OF THE INVENTION

To accomplish that goal, this invention contemplates a static poppingsystem which wholly recirculates air, reducing air escaping outside thecabinet, filtered or not. More particularly, one embodiment of theinvention uses two blowers producing separate and distinct airflow pathscontained within the popper cabinet. The first is a blower integral withthe filtering system for popping effluent. The second is a blower usedin maintaining the warm popcorn temperature after popping and prior toserving. By recirculating the air from both airflow systems within thepopper and reducing airflow escaping from open cabinet sides, nosignificant particulate components or emissions are emitted from thepopper cabinet.

This is accomplished in part through the use of air or effluent-flowcurtains sealing off leakages through the cabinet openings ofparticulate bearing emissions, as well as by recirculation of air withinrecirculated passages.

In the current improved embodiment, an intake ductwork is provided in arectangular “U” shape around the top underside of the cabinet and abovethe kettle level, thus allowing the particulate-laden steam to risenaturally into the internal vent ductwork. This allows for smallerfilters to be used to capture the particulates from that flow. This willalso reduce the force and speed with which the particulates pass throughthe filter media, allowing for a higher percent of particulate capture.Significantly, such filtered air, according to the invention, is notdischarged from the popper cabinet but rather is contained andrecirculated. Despite the efficiency of the filter media, there willstill be micro particles that will pass through the media on at leastthe recirculating first pass, thus another reason for recirculating thefiltered air. Each time the micro particles pass through therecirculation system, they will collide with other particles until mostof them coalesce to a size that can be captured and filtered out of theairstream.

With the recirculation of the filtered air, consideration is also givento the potential flow of the air through any open sides of the cabinet.In the interior of the cabinet is the popcorn kettle, either suspendedor pedestal mounted. The in-cabinet air flow is directed in such a wayas to miss the kettle so as not to create turbulence in the air flow. Asthe air is ducted back through the intake vents inside of the top wallof the cabinet, it is filtered and then divided into two paths by adistribution duct. The distribution duct divides the air equally intotwo curtain projectors located at the front and back of the popper nearthe corners. The curtain projectors each have a perforated cover whichproduces an air curtain blowing across the front opening of the cabinet(operator side), and in the case of an open pass through popper cabinetdesign, across the rear or back opening of the cabinet. These curtainsof air or of mixed air and effluent prevent particulates from escapingthrough the front or rear openings. The air flow curtains prevent anyturbulent air passing onto or adjacent the kettle from escaping thecabinet. Air bearing particulates are captured in the recirculationfilters, without significant effluent discharge therefrom.

A second source of air flow or second flow path in the cabinet comesfrom the popcorn warmer located in the bottom of the popper cabinetwhere the popped popcorn is held until served. The purpose of thissystem is to keep the popcorn at serving temperature and to keep it fromabsorbing moisture. In the earlier popper noted above, a long 800 watttubular element and a 105 CFM blower were used. The location of thiswarmer was at one end of the popcorn holding bin.

In the embodiment of the invention herein, a more compact 750 watttubular element and a compact 107 CFM blower are used. The location ofthis warmer is central to the holding area, allowing a more uniformdistribution of the heated air through the popped popcorn.

The intake duct on the earlier popper pulled outside air into the warmercabinet. In the new embodiment of the invention herein, the intake islocated above or at the top of the popped popcorn holding bin, thuspulling and recirculating the air from the warmer within the cabinet.This will also resolve the propensity of the old warmer design thatpulled chaff from the corn into the system.

A further benefit of the invention herein is in regard to firecontainment in the event a fire would ever occur. With the older popper,a fire damper was placed on the blower exhaust that depended on a linkto break at a given temperature to close the exhaust and prevent thefire from escaping through the exhaust. However, it was possible forflames to escape prior to the linkage reaching the necessary breaktemperature. With the design herein, recirculating the air back throughthe cabinet, there is no path to the exterior of the cabinet for thefire to escape. In addition, the air curtain across the front and rearopenings of the cabinet will keep any fire from escaping through thoseopenings until the extinguishing system douses the fire.

This invention thus contemplates an exhaust-less, self-contained orduct-less popcorn popper comprising a cabinet housing a popping kettleand a popcorn warming bin, the cabinet having at least an open side, oropening in a cabinet side, wherein recirculating air flows are createdwithin and about the cabinet for recurring filtration and wherein air isnot generally emitted or discharged from the cabinet, nor any openingthereto, thus reducing discharge of particulates from the poppingprocess. Such a popper can be installed and used without any externalventing or ductwork, and costs thereof, while meeting or exceedingcurrent standards for any particulate discharge and substantially lessthan 5 mg per cubic meter over an entire popping operation cycle ofeight hours or more.

These and other advantages will be readily apparent from the followingfurther details and from the drawings in which:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front elevational view of the invention;

FIG. 2 is a top plan view of the invention of FIG. 1;

FIG. 3 is a cross-sectional view taken along lines 3-3 of FIG. 1;

FIG. 4 is a cross-sectional view taken along lines 4-4 of FIG. 1;

FIG. 5 is a cross-sectional view taken along lines 5-5 of FIG. 1; and

FIG. 6 is a cross-sectional view taken along lines 6-6 of FIG. 2,illustrating further detail of the invention of the Figures.

DETAILED DESCRIPTION OF THE INVENTION

Turning now to the drawings, there is illustrated in FIG. 1 a poppercabinet 10 according to the invention having a front or operator side 12and an opposed parallel optionally open rear side 14, and two opposedclosed ends 16 and 18. A popped popcorn receiving open-top bin orchamber 20 is disposed in a lower portion of cabinet 10.

A tiltable popcorn popping kettle 22 of any suitable construction as iswell-known, is operably disposed within an upper portion of cabinet 10for popping popcorn and tilting to deposit popped popcorn intoopen-topped bin 20.

It will be appreciated that the sides 12, 14 of the cabinet are openfrom end 16 to end 18 in the upper portion of the cabinet 10 above bin10 so the kettle 22 and open top 24 of bin 20 (within cabinet 10) areeasily accessible to an operator through at least side 12 and optionallythrough an optionally open side 14.

Popped corn from kettle 22 is dumped into bin 20 for continued warmingand ultimate service therefrom by an operator through at least open side12.

It will be appreciated that while only one kettle 22 is shown, in analternate embodiment, another popping kettle can be oriented near end 16of cabinet 10 to provide higher capacity production, and in which casethe effluent containment construction to be described nearer cabinet end18 would preferably be duplicated near end 16. Such a second poppingkettle and effluent containment construction is not shown herein forpurposes of clarity.

For further definition, the reference to the upper position of thecabinet 10 refers to that portion of the cabinet above the top 24 of bin20, while the reference to the lower portion of cabinet 10 refers tothat portion of the cabinet 10 below the top 24 of bin 20.

Turning now to the effluent containment apparatus and function of theinvention, there is shown in respective FIGS. a blower 30, a primarydistribution duct 32, vertical curtain projectors 34, 36, intake vents38-40 (FIG. 4) an filter enclosure 42 housing any suitable air andparticular filters 44 and any suitable baffle filters 46.

Intake vents 38-40 are formed generally in a “U”-shaped configurationabout an upper portion of cabinet 10 and at a level preferably above thelevel of kettle 22 and proximate a top wall 27. These vents operablycommunicate through a plenum 48 (FIG. 6) with filter housing 42, suchthat air and effluent from the popping operation flows into vents 38-40,through plenum 48, filters 46, 44, blower 30 and distribution duct 32 tovertical air curtain projectors 34, 36. One or more filters can be usedas needed or desired, several being shown in FIG. 6 for exemplaryillustrating. Projectors 34, 36 are preferably perforated or are fittedwith nozzles, in combination producing an air or effluent curtain acrossthe open side 12 (and side 14) of cabinet 10. Preferably the respectiveair curtains so produced are angled from the respective projectors 34,36 slightly inward toward the inside of cabinet 10, thus are preferablynot parallel but respectively inclined inwardly toward each other.Arrows A in FIG. 6 illustrate the flow of one curtain from verticalprojector 34. It will be appreciated that effluent from kettle 22naturally rises toward the top of cabinet 10, but is further pulled intointakes 38-40.

Filter access cover 45 (FIG. 4) provides access to filters 44, 46 forcleaning or replacement.

Air flow from projectors 34, 36 travels first across, then upwardly intovents 38-40 to complete the flow circuit.

Effluent from the popping of popcorn in kettle 22 tends also to rise forcapture within vents 38-40.

A flower divider in plenum 32 separates the flow of now filtered airinto two streams, respectively, toward projectors 34, 36.

As previously stated, the velocity of the air flow projected fromprojectors 34, 36 is effectively produced in cabinet 10 from any furthersuitable blower 30 having an output capacity as required to draw ineffluent from kettle 22 and blow it eventually through projectors 34, 36to create the desired air curtains. A blower of any suitable capacity isused to provide this air flow. This has at least two beneficial effects;it allows the use of small filters (relative to those used in priorpoppers where flows are higher) and it maintains the air curtainvelocities at relatively low speeds which do not produce unnecessaryturbulence leading to escape of particulate containing effluent. Theoverall effect is to provide a high percent of particulate capture andto retain air flow within the cabinet 10 so no measurable effluentparticulates are projected into the environment around the cabinet 10.

Thus, there is no need for hoods or venting ductwork outside or abovecabinet 10, even in a large capacity commercial popping operation.

It will be appreciated that it is not believed necessary to define thepopping chamber about kettle 22 with wholly confining air curtains, itonly being desirable to create air curtains across the open sides 12, 14of the upper portion of cabinet 10, and to capture effluent flow withinthe “U”-shaped vents 38-40. This construction and flow efficientlycaptures particulate-bearing effluent from the popping operation andfilters it with a recirculating flow, without escape outside cabinet 10.

If desired, an additional curtain projector could be placed across thecenter of the cabinet between sides 12 and 14 and directed upwardlytoward parallel vent 39, but such additional air curtain is not believednecessary to the objective of efficiently containing and recirculatingparticulate-bearing effluent.

In another aspect of the invention, warm, heated air is circulatedthrough popped popcorn in bin 20 and recirculated therethrough withoutescape of such air to the outside of cabinet 10. Bin 20 is an enclosedbin having an open top 24 within cabinet 10. A warmer plenum or housing60 houses a suitable heating element, such as a 750 watt tubular heater,and a blower, such as a 107 CFM blower, neither being shown. Warm air isprojected from plenum 60 into bin 20 and popped corn therein in thedirection of arrows B and C. Such warm air flows upwardly then backtoward intake duct 62 and downwardly toward the blower and heateroperably connected to distribution duct 60 (arrows D).

Such heated air is recirculated through bin 20 and popcorn therein anddoes not escape from cabinet 10.

It will be appreciated that even though the entire side 12 of the upperportion cabinet 10 is open, and even though side 14 may be likewiseopen, the invention captures and recirculates effluent from a popcornpopping process, and filters it so few effluent-bearingprocess-generating particulates escape from the cabinet. Thus, thepoppers according to this invention can be installed and retrofittedinto theaters and other concerns without the need for additional hoods,venting ductwork or associated costs; no measurable particulate-bearingeffluent being released from the cabinet.

The invention thus includes a popcorn popper including a cabinet with atleast one open side, an air curtain extending across at least a portionof said open side, air intake vents disposed at a level above a level ofa popping kettle within the cabinet and an effluent recirculating flowpath from said air curtain, to the air intake vents, filter, blower andback to the air curtain. Warm air is recirculated through a warmer binin a lower portion of the cabinet.

Vent hoods and ductwork are thus eliminated along with measurableparticulate-bearing effluent from a popper cabinet.

As used herein, the term kettle includes a heatable popcorn poppingkettle as in U.S. Pat. No. 7,874,244, or any device for popping popcornand however constructed for applying heat to unpopped popcorn, includingby convection, conduction or otherwise.

As used herein, the phrase “air curtain projector” includes any deviceor structure for establishing a curtain or a flow of air across an openportion or side of a cabinet containing a popcorn popping kettle. Such aprojector includes, but is not limited to, a perforated duct, aplurality of nozzles operably extending from or mounted on an air plenumin combination producing an air curtain, a slotted plenum, an air knifeor any other suitable structure for establishing a flow of air across anopen cabinet side. The projector is a component of an air recirculationsystem including an intake vent, filters and distribution duct fordirecting filtered effluent to said projector.

As used herein, the term “effluent” includes steam, vapor, oil vapor andparticulates emitted from a popcorn popping operation and including air.As described herein, particulates in the effluent from a popcorn poppingoperation are progressively filtered from the effluent and any airconstituent thereof as the effluent is passed through filters in arecirculation loop.

It will be appreciated that operation of the popper herein withoutactually popping popcorn results in a recirculating air flow from theblower into and through a distribution ductwork, through an air curtainprojector and into intake vents and through a filter system back to theblower substantially without emission of the air from the cabinetdefining the popper. When popcorn is popped in the kettle, effluent fromthe popping operation is entrained in such air flow and is recirculatedtherewith.

It will further be appreciated that alternatively to the abovedescription, the invention contemplates a popcorn popper wherein the aircurtain flow is produced by a blower and an air flow of fresh,non-effluent air.

In such a system, an air intake would be ducted to the air curtainprojectors to create the curtains, preventing escape of poppingeffluent, while popping effluent would be sucked into intake vents suchas at 38, 39 and 40, recirculated through filters such as shown in thesedrawings and directed back into the cabinet at any suitable location forrecirculation but captured within the cabinet without dischargetherefrom. Other intake vents could be located to receive andrecirculate, or to discharge, the fresh air from the air curtain flow,again without significant effluent escape.

Thus, the air curtain would comprise unfiltered, but fresh air, whileeffluent containing air would be recirculated within the cabinet.

In a slight variation, air within the cabinet, and containing effluent,could be introduced into the air curtain without prior filtration withsplitting of air flow to a filtration path for recirculation and to anunfiltered path for air curtain production, all while capturing thebenefits of the preferred embodiment described above.

It will also be appreciated that any air or mixed effluent which mightbe incidentally emitted or separated from the cabinet or therecirculating flow contains less than the regulatory permitted contentof particulates now defined as less than 5 milligrams or particulate percubic meter of air; while preferably no effluent escapes from thecabinet. Thus, as used herein, terms like substantial and significantare used to descriptively to refer relatively to ranges of effluent orparticulates discharge according to the invention below such amounts aswould be regulatorily prohibited.

What is claimed is:
 1. A method of popping popcorn in a cabinet havingat least one open side and including the steps of: popping popcorn insaid cab and producing effluent from said popping; establishing an aircurtain across at least a portion of said open side and obstructingescape of effluent therethrough; and recirculating effluent from saidpopping through a filter and into said air curtain.
 2. A method as inclaim 1 including passing said effluent into a vent disposed at an upperportion of said cabinet, filtering said effluent and passing filteredeffluent to said air curtain and then into said intake vent.
 3. A methodas in claim 1 including establishing said curtain in a directioninclined inwardly across said portion of said open side.